Carburetor



HENNING CARBURETOB Jan. 17, 1939.

Filed may 1934 I FIGJ OTTO H 2 Sheets-Sheet l Um I" NING INVENTOR 7 I31 FIG. 5

BY MM ATTORNEY Jan. 17, 1939. o. HENNING 2,144,153 7 CARIBURETOH Filed May 18, 1934 2 Sheets-Sheet 2 OTTO HENNING HQ 4 r mmvrox Patented Jan. 17, 1939 UNITED STATES CARBUBETOR Otto Henning, Detroit, Mich, assignor to Carter Carburetor Corporation ration of Delaware,

Application May 18, 19

9 Claims.

This invention relates to carburetors for in ternal combustion engines and more particularly to devices for controlling closing movements of the throttle to prevent roughness in the operation of the engine under certain conditions.

'Prior to my invention, the operation of internal combustion engines, more especially those mounted in rubber, was frequently uneven. If the engine is operating at a comparatively high speed, the torque developed is high and there is a tendency for the engine to move to one side, generally to the right. If now, the operator closes the throttle quickly, shutting off the supplyof gasoline to the engine, the speed will be rapidly decreased and the engine will tend to move to the opposite side. When the speed is decreased rapidly this movement in the opposite direction is very rapid and results in a shock. This shock is not taken up entirely by the rubber mountings and is thence transmitted to the various parts of the car providing discomfort to the occupants and strain on the entire automobile.

I have found that this shock could be prevented by a means for resisting the rapid closing action of the throttle, thus decreasing the gasoline supply to the engine at a slow rate, whereby the torque and the speed are decreased'more slowly allowing the engine to move to its new position without a shock to the car.

In accomplishing the above object I have provided a dash pot constructed in such a way as to allow ..rapid opening of the throttle, but preventing rapid closing.

A better understanding of my invention will be had by'referring to the drawings in which:

Figure 1 is a side elevation of a down-draft carburetor with my invention added thereto, parts being broken away and others shown in section.

Figure 2 is a view similar to that in Figure 1 of the lower portion of the carburetor, parts being removed or broken away to show other parts more clearly.

Figure 3 is an end elevation of the carbureto parts being broken away.

Figure 4 is an enlarged sectional view of the plunger as shown in Figure 1.

Figure 5 is a detail view showing the same parts as shown in the lower part of Figure 1,but in a different operating position. r

The reference numeral I refers to the body of a down-draft carburetor of well known design and structure, having the customary float bowl 2, air horn 3 containing choke valve (not shown) operated by lever arm 4 and choke wire 5. The carburetor contains the usual float mechanism v.relation to the shaft.

, St. Louis, Mo.; a corpo- 34, Serial No. 726,274

already well known .to the art and not shown in the drawings. K

The throttlevalve 6, shown by dotted lines in Figure 1, is mounted on a shaft 1 and is operated manually 'by the lever arm 8, also mounted on 5 the shaft 1, and the link 9 attached by conventional means thereto. Loosely'mounted near the outer extremity of the shaft 1 is an arm l0, having a downwardly extending ear Ii near thelower end of which is a hole I2 and near the upper end 0 a hole to which the link I9 is attached. The arm H) has a forwardly projecting lug l3 extending from its upper edge. At the extremity of the shaft 1 a lever I 4 is rigidly mounted. The lever I4 is of well known design. The lever i 4 and the lever Ill are interconnected by means of a spring 50, one end of which is hooked into the hole l2 and the other end into a hole 5| in the lever It as shown in Figures 1 and 3.

The lever I4 is connected to the rocker arm [6 0 by the link IS. The rocker arm I 6 is connected to the piston ll of the accelerating pump diagrammatically indicated at 63 by the link l8. A spring, diagrammatically indicated at 60, is connected to the throttle operating mechanism as 25 for instance to the pin iii, the other end being anchored as at 62, for yieldably closing the throttle.

The bracket is held in position with relation tothe body of the carburetor by means of screws 30 2!. In the bracket His a shaft 22 on which is loosely mounted the rocker arm 23 to; one end of which is connected the link l9 and to the other end the link 24. The link 24 is in turn connected to the plunger shaft 25.

The-lower end of the shaft 25 contains a vertical passage 26 relatively large in diameter with The upper end of passage 26is made smaller in diameter forming the valve seat 21 and the still smaller passage 28. Drilled 40 horizontally across the diminished passage 28 is a passage 29 extending through the shaft 25.

A ball check valve 30 is held in position by the pin 3|. Below the pin 3| a passage 32, of smaller diameter than thatof passage 29, is drilled hori- 4;, zontally into-the passage 26. Riveted over at the lower extremity of the plunger shaft 25 are two metal washers 33 which secure the leather plunger 34. The plunger assembly is contained in a housing 35 mounted in the under side of the float bowl 2 by means of threads 38 and made gasoline tight by the gasket 39. The floor 36 of the housing 35 has an annular extension. 31 raised to serve as a stop for the plunger, thus preventing the crushing of the plunger leather it against levers i and I4.

the floor 36 of the housing when the plunger is lowered. The plunger shaft 25 passes through a passage 40 of substantially larger diameter than the plunger shaft. This passage 40 is in the floor ll of the float bowl 2.

' It will be noted that the rocker arm 23, as shown in Figure 1, has the right side or that to which the plunger is connected much longer than the left side or that to which the lever I6 is joined through the link IS. The plunger will thus travel its full stroke while the lever l0 travels through a comparatively small arc, approximately 20 degrees.

In operation, when the throttle valve 6 is opened manually the lever I4 is rotated clockwise with respect to Figure 1' raising the link l and operating the accelerating pump as inprevlous constructions. As the lever ll rotates clockwise the tension on the spring 50 is increased rotating the lever ID in a clockwise manner, lowering the link is. With respect to Figure 1 the right side of the rocker arm 23 is thereby lowered and the left side raised. Consequently the plunger shaft 25 is correspondingly lifted. This upward motion allows the ball check valve 36 to open admitting gasoline fromthe bowl via passages 40, 29, 32 and 26, respectively to the under side of the plunger. As the throttle is farther opened after the plunger has reached the top of its stroke, the lever l4, rotation thereof being continued-in a clockwise direction, leavesits contact with the lug l3 and the lever I0 is stationary. I

On closing'the throttle, the lever I4 isrotated in a counterclockwise manner with respect to Figure l. of lever ll contacts the lug l3 when within approximately degrees of closed position rotating the lever III in a counterclockwise manner with respect to Figure 1,-raising the link I9. Thereby, the plunger shaft is lowered by means of the rocker arm 23., The lowering motion of the plunger causes the pressure of the gasoline to close the ball check valve against its seat 21. The only outlet for the gasoline contained in the housing 35 below the plunger is the comparatively small passage 32. The slow rate of fiow of gasoline through the restricted passage 32 prevents the plunger from being lowered rapidly which in turn prevents rapid counter-clockwise motion of Lever l4, being rigidly mounted on the throttle valve shaft '1, rapid closing of the throttle valve 6 is resisted during approximately the last 20 degrees of its closing.

The invention is not limited in details to the structure shown but may be modified in various respects as will occur to those skilled in the art and the exclusive use of all such modifications that come within the scope of the appended claims is contemplated.

I claim:

1. A dash pot plunger comprising a. shaft, said shaft having a longitudinal passage extending into one end thereof, a reduced portion being formed on the exterior of said shaft near said last named end thereof, the inner portion of said passage being of smaller diameter than the outer portion, the junction of the two portions forming a valve seat, a valve for closing said passage at said valve seat, a transverse bore in said shaft connecting with the smaller portion of said first named bore, and a piston mounted on said reduced portion of said shaft and spaced longitudinally of said shaft from said transverse bore, the end of said shaft being riveted over to hold said piston in position.

As shown in Figures 1 and 3 the edge 2. A dash pot plunger comprising a shaft, said shaft having a longitudinal passage extending into one end thereof, a reduced portion being formed on the exterior of said shaft near said last named end thereof, the inner portion of said passage being of smaller diameter than the outer portion, the junction of the two portions forming a valve seat, a ball check valve for closing said passage at said valve seat, a transverse bore in said shaft connecting with the smaller portion of said first named bore, a piston mounted on said reduced portion of said shaft, the end of said shaft being riveted over to hold said piston in position, and a small passageway formed 'in said shaft inwardly of said piston and communicating with the larger portion of said first named bore.

3. A dash pot plunger device comprising a shaft having a longitudinal orifice extending into an end portion thereof, a transverse bore in said shaft and communicating with said orifice, a piston on said end of said shaft and spaced toward said end from said bore, a valve seat in said orifice, a valve associated with said seat, and a second transverse bore in said shaft and communicating with said orifice on the opposite side of said valve seat from said first mentioned bore, the smaller cross sections of said transverse bores being of substantially different sizes whereby fiuid may pass through one of said bores more easily than through the other.

4. In a carburetor, a throttle valve, a throttle valve shaft, an accelerating pump, means for connecting said throttle valve and said pump comprising in part a lever rigidly mounted on said throttle valve shaft, a dash pot device including a plunger, a lever loosely mounted on said throttle valve shaft, means for connecting said dash pot plunger to said loosely mounted lever, means for connecting said loosely mounted lever to said rigidly mounted lever for non-yielding movement of said dash pot plunger in one direction during closing movement of said throttle valve, and yielding means connecting said lever for movement of said plunger in the other direction during opening movement of said throttle valve.

5. The combination of elements specified in claim 4 in which said dash pot device includes bypass structure whereby said device applies substantially greater resistance to closing movement of said throttle than to opening movement of said a throttle.

6; The combination of elements specified in claim ,4 in which said accelerating pump is arranged to resist closing movement of said throttle valve in addition to the resistance offered to such movement by said dash pot plunger.

7. In a carburetor, a throttle valve, and a dash pot device operatively associated with said valve, said device comprising a fluid chamber, a plunger formed of a piston rod and a piston movable in said chamber, there being a longitudinal orifice in said rod. opening into said chamber on both sides of' said piston, and a check valve in said orifice, said check valve being arranged to closesaid orifice when said piston is moved in one direction whereby said device substantially retards corresponding movement of said first mentioned valve.

8. The combination of a carburetor having a throttle valve, actuating. mechanism for said throttle valve including means for normally moving the valve towards closed position, a retarding device, means connecting the retarding device with said throttle actuatingmechanism for moving said device to its operative position during predetermined movements of said mechanism,

and means for connecting said retarding device tarding device, means actuated by the valve opening mechanism for moving the retarding device into operative position, and means for connecting the retarding device with the throttle valve during a. predetermined period of its movement.

OTTO HENNING. 

